Test procedures for cleanroom products

Festo products for cleanrooms

FAQ and practical tips

In the past, very few industries used cleanrooms for their production. Today, however, cleanroom production has extended beyond electronics and photovoltaic manufacturing, medical technology and the semiconductor industry. Numerous other industry sectors also need components that are suitable for use in cleanrooms. Click here to find the most important information.

Which products does Festo offer for use in cleanrooms?

You can use all Festo cylinders, valves, grippers and drives, all handling, vacuum and compressed air systems, sensors, filters, compressed air regulators and fittings from more than 80 product ranges in ISO class 7 cleanroom environments. Most are suitable for use in classes 6 and 5, and many can even be used in class 4 environments. We can also provide customised special solutions.

All our cleanroom products are classified into cleanroom classes according to ISO 14664. It’s best to check the exact requirements with our specialists, because particle emissions depend on the application in question. That’s the quickest way to find a workable solution.

Useful information about cleanrooms

Does Festo only have standard cleanroom products?

Not at all. There are always applications where standard solutions no longer fit the bill. For example, when the cleanliness requirements are so strict that only a special solution can be used. We can help here, too. A simple modification is often all it takes. It’s best if you contact our experts directly in cases like this.

Adapted special solutions

We have more than 20 years of cleanroom experience and our engineers continuously adapt series components in order to make them suitable for use in class 4 or stricter environments in accordance with ISO 14664.

We use a tried-and-tested two-stage consultation concept in which we listen to you and address the problem together. Highly sensitive zones can often be isolated, outside of which an ISO class 5 or 6 component will suffice. Our engineers put everything together and submit a solution to you, along with a quote.

How does Festo qualify cleanroom products?

Cleanroom: test procedures for cleanroom products

Our products are tested and qualified by certified institutes according to ISO 14644. You can read about how the measurements are carried out in the test reports. Here you can find out, for instance, what the operating conditions during the test were and which test equipment was used.

How is the test carried out?

We clean the products with isopropanol and ultrapure air, carry out visual checks and then have them tested. Our test samples come directly from Festo stock, so we don't preselect them as is the case with other suppliers.

How are cleanroom products classified?

You can rest assured that cleanroom solutions from Festo are tested and classified according to ISO 14644-1. ISO 14644 divides cleanrooms into nine classes according to the number and size of airborne particles.

Please note: our classification only provides an indication of how you can use our products in cleanrooms. If there is any doubt, we recommend performing the tests under real conditions.

How do I find suitable cleanroom products?

To ensure that you quickly arrive at a functioning cleanroom application, we’ve compiled all tested components from more than 80 of Festo’s product ranges in our cleanroom catalogue. These include all types of pneumatic drives, valves and valve terminals, compressed air preparation and accessories, as well as electric drive technology. This is generally sufficient.

Cleanroom catalogue plus X

If you’re interested in a product that we haven’t tested yet for its cleanroom compatibility, we’d be happy to test it for you on request. Our specialists are always happy to answer any other questions you might have, and can also quite easily adapt particular products to be suitable for ISO class 4.

What should be considered when using cleanroom products?

The most important criterion is that the products comply with the specified cleanroom class during operation. That’s what really counts. All cleanroom products from Festo are certified in accordance with the VDI standard and classified to ISO 14644-14. However, the cleanroom class depends on where in the application the product is used. This sounds complicated but is actually good news.

Cleanroom class according to location of use

The fact that the cleanroom compatibility of operating equipment always depends on where it’s used means that you don’t have to implement stricter cleanliness everywhere. Cleanrooms are not homogenous zones. Maybe you need ISO-14644-14 class 5 directly above the workpiece, while class 7 is enough for the rest of the workflow. In other words, the standard products from Festo fulfil the requirements in most cases.
The same positive answer also applies to cleanroom compatibility for packaging. Technically correct cleanroom packaging is possible with Festo, but it’s seldom really necessary and represents a cost factor that you can often do away with. Our experience shows that most components can be assembled and prepared for shipping in a normal environment. Final cleaning takes place directly on-site.
Don’t hesitate to get in touch with us if you have any doubts. For example, if the component needs to fulfil a safety function or if your ambient conditions differ from the values listed in the data sheet.

Tips for cleanroom design

End-position switch

Double-acting cylinder with cables for proximity sensors

When wiring the end-position switches of double-acting cylinders, you need to make sure that you can’t move the cables and that they don’t rub against each other or any other equipment.

Cylinder cushioning

Cushioning PPV and PPS in the compact cylinder

You should avoid high-force impacts in the end position. That's what cylinder cushioning is for. Adjustable and self-adjusting PPV and PPS variants significantly reduce particle emissions.

Single-acting cylinder

Double-acting cylinders compared with single-acting cylinders

It’s better not to use single-acting cylinders because particles are discharged into the atmosphere via the exhaust. The piston rod seal is also considerably thicker in double-acting cylinders.

Bellows actuators

 Electromechanical bellows actuator

The cylinder fittings are leak-free when correctly assembled [1]. The piston rod seal, on the other hand, is a source of particle contamination due to its design. A bellows or vacuum exhaust can therefore be helpful [2].

Mechanical abrasion

Double-acting cylinder

You should avoid using rod eyes [1], rod clevises, flexible couplings and swivel flanges [2] since they generate abraded particles. Make sure that tubing doesn’t move or rub against anything.

Vacuum applications

Rotary drive

In the case of vacuum applications, it is advisable to use our rotary drives. This is because rotary motion is easier to seal than linear motion, and is therefore more suitable.

Compressed air preparation

Compressed air preparation with filters

Fine particulates and contamination should be filtered out in several stages during compressed air preparation. We recommend using a filter cascade with 40 [1], 5 [2] and 1 µm [3] stages in cleanrooms.

Exhaust air

Valve terminal

The pilot air for valves is hardly ever of any importance [1]. In contrast, exhaust air always has to be contained and must not be discharged into the cleanroom via silencers [3]. When correctly mounted, fittings are leak-free [2].

Spindle axes

Spindle axis for cleanrooms

Spindle axes are better suited for cleanrooms than toothed belt axes; they cause less abrasion and discharge fewer particles. Furthermore, the spindles are greased and thus the abraded particles stick to them.

Energy chains

Energy chains for cleanrooms

Standard energy chains are critical in cleanrooms. Although there are special energy chains for cleanrooms, it's generally better to ensure during the design phase that the handling unit is placed where possible underneath the workpiece.

And last but not least: when it comes to cleanroom compatibility at Festo, we always assume that closed, monitored compressed air systems are being used, without leakages and without particles being discharged into the environment by the exhaust air.

It’s important to note that our components are not suitable for conveying (using tubing and fittings) or switching (using valves) purified air! Our fine filters and micro filters are the only exception, since they generate highly purified air depending on the grade of filtration.

Who else needs to know this?

Cleanroom engineering is really quite an art. You should make sure that everyone involved has all the necessary information right from the planning phase. The quickest way is to use this link.